Recently, genetic manipulation has been frequently performed not only in animals but also in plants due to the development of biotechnology. When such genetic manipulation is performed, suitable vectors are usually chosen depending on types of host living organisms. In such vectors, markers are usually incorporated into host cells in order to know whether or not desired genes are incorporated into host cells. For example, a kanamycin resistance gene, a chloramphenicol resistance gene, and the like are used as representative markers.
However, it is necessary to pay a special attention in handling antibiotics corresponding to these drug-resistance markers from the viewpoint of medical and environment safety.
Therefore, it has been desired to establish vectors having relatively safe drug-resistance markers.
Furthermore, it is desired to attain more efficient agricultural production by producing useful plants having drug resistance against specific agricultural chemicals.